By looking at the diagram below, you can see the structural changes that occur within the plant as it progresses through different stages of growth.
Diagram 1 Stages of Plant Growth
During the vegetative stage the plant is green and lush, with the cell wall being very thin in relation to the cell content. This means the fibre and lignin content is low, and the energy, protein and starch levels are high. As the plant continues to grow and begins to flower and seed, the cell walls become thicker and cell content decreases, meaning less energy, starch and protein and an increase in lignin and fibre. As the plant matures and dries out the cell content is greatly reduced and the cell wall basically makes up ?_ of the plant, meaning the levels of protein, energy and minerals are very low, and lignin, fibre and indigestible fibre are high.
When there is abundant protein and low lignin, the microbial population in the rumen is able to multiply due to excess protein that?۪s available. This increases the rate of digestion which increases daily consumptions, and in turn increases daily weight gains. On the other hand, when the grass is dry and highly lignified the rumen microbes have access to a much lower level of energy, protein, minerals and vitamins for their own maintenance and reproduction, which therefore decreases the rumen microbe population and ultimately slows the digestion of the low quality pasture.
This slower rate of digestion causes a decrease in the quantity of feed that can be ingested per day, so not only is the pasture low in energy and protein, it is also hard to breakdown and digest. When cattle need to consume more feed per day to make up for the low level of metabolisable energy and protein available in the pasture, they are unable to do so due to the slow breakdown and slow digestion rate of the highly lignifies and fibrous forage. This results in the animals?۪ daily maintenance requirements not being met, causing weight loss.
The diagram below reiterates how the levels of energy, protein and fibre alter through different stages of growth
To combat this effect, supplementation through the use of dry licks is an excellent strategy to reduce the impact of production loss during the period of low quality pastures. Consumption rates of 200-300g of dry lick supplement per head per day will increase the utilisation and digestibility of poor quality pastures through increased rate of passage. This allows the animal to achieve higher intakes of dry matter, therefore increasing available energy and protein intakes. As a result of this not only do the cattle benefit directly through improved/maintained body condition, increased lactation, higher fertility rates and improved growth, paddocks are grazed more evenly as cattle are able to feed on those patches of older tougher forage which then allows fresh new growth the opportunity to emerge in the wet season.
It is also essential to keep in mind that supplementation doesn?۪t have to wait until you notice cattle already starting to lose condition. It is much more efficient to be proactive and start supplementation before you see a loss in condition as when you leave it too late, it is a long road to try and bring them back rather than just starting early and holding their condition.
Sometimes it is hard to make the call on when to start supplementing, as we cannot predict what the season will do, and we all know the weather man cannot be relied on to supply us with accurate information. The nutritionists at Top Country are here to assist graziers in making this decision, and can prepare a program to suit each individual situation. We have many different products that are tailored to achieve different goals and outcomes, and to suit the changing pasture quality throughout the ever changing seasons.
Transition supplements are designed to meet stocks?۪ requirements for protein while there is still a portion of green pasture left. As pastures hay off, protein levels and feed quality drop while fibre increases. Strategic protein and mineral supplementation at this time alleviates pressure from decreasing pasture quality on stock as they go into winter. Top Country nutritionists aid graziers in preparing a program to flatten out this dip in production over pasture transition phases by supplementing with situation specific products. Top Country?۪s Top Fos range is suitable for supplementing cattle, sheep and goats as pastures mature and hay off. High in minerals while supplying reasonable levels of protein in the form of meals and NPN sources, this range is very versatile and can be adjusted to suit each individual situation.
Give the nutritionists at Top Country a call to discuss your supplementation program today.
Author: Pippa Hodgson